A request from the U.S. for Canada to step up its involvement in the military campaign against the extremist group, which has swallowed a vast swath of territory in the war-racked Middle East, was the subject of a flurry of closed-door presentations and a lengthy exchange in the House of Commons.
The contribution — at this stage — would involve a contingent of CF-18 fighters and surveillance aircraft. That would be in addition to the 69 special forces troops committed to the mission in northern Iraq, whose participation is subject to review and renewal by the end of the week.
"If there is a combat mission of any kind, including an air combat mission, there will be a debate and vote in this House," Harper said in answer to a series of questions from NDP Leader Tom Mulcair.
Harper said a final decision would come within days, but he left little doubt where the government was headed, telling Liberal Leader Justin Trudeau that "whenever we enter a mission that involves combat, including aerial combat," MPs will be consulted.
And finally, he said: "We will come to the House of Commons with a proposal on that matter and I look forward to a debate and vote on that."
For much of question period, the prime minister was peppered with questions as both Opposition parties demanded to know the case for war, how long it would last and what kind of restrictions would be placed on forces involved.
Harper set the stage for the forthcoming debate with a broad description of ISIL atrocities committed throughout Syria and northern Iraq against minority religious groups — and one pointed, ominous warning for Canadians.
"We have at the present time the establishment of a quasi-state, an Islamic caliphate, stretching from Aleppo almost to Baghdad, up until very recently operating entirely in the open, planning attacks, not just genocide against large populations in the region but planning attacks against this country," he said.
The notion that ISIL poses an imminent national security threat to Canada stands in contrast to the official position in the U.S., which said late last week that it does not consider the group to be a domestic threat, but rather a major, long-term risk to the West.
U.S. intelligence officials made the comment while attempting to justifying a concurrent airstrike against a separate terrorist network, the Khorasan group, a shadowy splinter of seasoned al-Qaida fighters.
In one of its recent propaganda videos, ISIL called on Muslims to rise up and kill not only Americans, but French, Australian and Canadian citizens. It's not clear if that was what was Harper was referencing in his remarks in the Commons.
U.S. Homeland Security Secretary Jeh Johnson was in Ottawa on Tuesday, where he met with Harper. He described ISIL's capacity to organize training camps for future attacks as a "serious, potential threat" to both his country and Canada.
"They've demonstrated a willingness to kill innocent hostages for the purpose of making a point in a depraved and public manner," Johnson said.
"They have a reach that is quite concerning."
NDP defence critic Jack Harris accused the government of fear-mongering.
Harper said the government is weighing Canada's capacity to contribute to the existing combat mission — an important consideration given the age of the country's fighters and the air force's ability to keep more than one deployment going at the same time.
The air force is heavily committed to North American air defence through Norad and an air defence mission over the Baltic states.
- With files from Jim Bronskill
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